TY  - JOUR
A1  - Mehnert, Jan
A1  - Brunetti, Maddalena
A1  - Steinbrink, Jens
A1  - Niedeggen, Michael
A1  - Dohle, Christian
T1  - Effect of a mirror-like illusion on activation in the precuneus assessed with functional near-infrared spectroscopy
JF  - Journal of biomedical optics
N2  - Mirror therapy is a therapy to treat patients with pain syndromes or hemiparesis after stroke. However, the underlying neurophysiologic mechanisms are not clearly understood. In order to determine the effect of a mirror-like illusion (MIR) on brain activity using functional near-infrared spectroscopy, 20 healthy right-handed subjects were examined. A MIR was induced by a digital horizontal inversion of the subjects' filmed hand. Optodes were placed on the primary motor cortex (M1) and the occipito-parietal cortex (precuneus, PC). Regions of interest (ROI) were defined a priori based on previous results of similar studies and confirmed by the analysis of effect sizes. Analysis of variance of the ROI signal revealed a dissociated pattern: at the PC, the MIR caused a significant inversion of a hemispheric lateralization opposite to the perceived hand, independent of the moving hand. In contrast, activity in M1 showed lateralization opposite to the moving hand, but revealed no mirror effect. These findings extend our understanding on interhemispheric rivalry and indicate that a MIR is integrated into visuomotor coordination similar to normal view, irrespective of the hand that is actually performing the task. (C) 2013 Society of Photo-Optical Instrumentation Engineers (SPIE)
KW  - functional near-infrared spectroscopy
KW  - optical imaging
KW  - mirror illusion
KW  - mirror therapy
KW  - precuneus
Y1  - 2013
U6  - https://doi.org/10.1117/1.JBO.18.6.066001
SN  - 1083-3668
VL  - 18
IS  - 6
PB  - SPIE
CY  - Bellingham
ER  - 
TY  - JOUR
A1  - Mehnert, Jan
A1  - Akhrif, Atae
A1  - Telkemeyer, Silke
A1  - Rossi, Sonja
A1  - Schmitz, Christoph H.
A1  - Steinbrink, Jens
A1  - Wartenburger, Isabell
A1  - Obrig, Hellmuth
A1  - Neufang, Susanne
T1  - Developmental changes in brain activation and functional connectivity during response inhibition in the early childhood brain
JF  - Brain and development : official journal of the Japanese Society of Child Neurology
N2  - Response inhibition is an attention function which develops relatively early during childhood. Behavioral data suggest that by the age of 3, children master the basic task requirements for the assessment of response inhibition but performance improves substantially until the age of 7. The neuronal mechanisms underlying these developmental processes, however, are not well understood. In this study, we examined brain activation patterns and behavioral performance of children aged between 4 and 6 years compared to adults by applying a go/no-go paradigm during near-infrared spectroscopy (NIRS) brain imaging. We furthermore applied task-independent functional connectivity measures to the imaging data to identify maturation of intrinsic neural functional networks. We found a significant group x condition related interaction in terms of inhibition-related reduced right fronto-parietal activation in children compared to adults. In contrast, motor-related activation did not differ between age groups. Functional connectivity analysis revealed that in the children's group, short-range coherence within frontal areas was stronger, and long-range coherence between frontal and parietal areas was weaker, compared to adults. Our findings show that in children aged from 4 to 6 years fronto-parietal brain maturation plays a crucial part in the cognitive development of response inhibition.
KW  - Optical tomography
KW  - NIRS
KW  - Response inhibition
KW  - Functional connectivity
KW  - Development
KW  - Early childhood
Y1  - 2013
U6  - https://doi.org/10.1016/j.braindev.2012.11.006
SN  - 0387-7604
SN  - 1872-7131
VL  - 35
IS  - 10
SP  - 894
EP  - 904
PB  - Elsevier
CY  - Amsterdam
ER  -